Patents by Inventor Hirofumi Natsume

Hirofumi Natsume has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Glass antenna system for automobile
    Patent number: 5699071
    Abstract: A glass antenna system for an automobile comprises a T-shaped or pi-shaped dynamic impedance matching circuit. Another system comprises an integrated circuit consisting of T-shaped FM and AM matching circuits each connected to a common cable. The T-shaped or pi-shaped matching circuit comprises at least two varactor diodes each applied to a channel selection voltage to match the FM antenna impedance with that of the FM receiver including that of the transmission cable.
    Type: Grant
    Filed: June 3, 1996
    Date of Patent: December 16, 1997
    Assignees: Sumitomo Chemical Company, Limited, Nippon Sheet Glass Co., Ltd.
    Inventors: Kanta Urakami, Nobuya Niizaki, Hirofumi Natsume, Masato Arisawa, Harunori Murakami, Yuji Baba
  • Glass antenna system for automobiles
    Patent number: 5602558
    Abstract: A glass antenna system for an automobile comprises a T-shaped or pi-shaped dynamic impedance matching circuit. Another system comprises an integrated circuit consisting of T-shaped FM and AM matching circuits each connected to a common cable. The T-shaped or pi-shaped matching circuit comprises at least two varactor diodes each applied to a channel selection voltage to match the FM antenna impedance with that of the FM receiver including that of the transmission cable.
    Type: Grant
    Filed: June 2, 1995
    Date of Patent: February 11, 1997
    Assignees: Sumitomo Chemical Company, Limited, Nippon Sheet GLass Co., Ltd.
    Inventors: Kanta Urakami, Nobuya Niizaki, Hirofumi Natsume, Masato Arisawa, Harunori Murakami, Yuji Baba
  • Glass antenna for automobile
    Patent number: 5334988
    Abstract: A glass antenna for an automobile uses a coil connected directly to a bus for defogging heaters as an FM subsidiary antenna and a T-shaped impedance matching circuit to provide a monotone change of impedance within the FM frequency band. A reverse T-shaped FM main antenna is employed in conjunction with the FM subsidiary antenna to provide a diversity system to enhance receiving sensitivity in entire directions. The T-shaped matching circuit comprises at least two varactor diodes each applied to a channel selection voltage to match the FM antenna impedance with that of the FM receiver including that of the transmission cable.
    Type: Grant
    Filed: March 25, 1992
    Date of Patent: August 2, 1994
    Assignees: Nippon Sheet Glass Co., Ltd., Sumitomo Chemical Company, Ltd.
    Inventors: Harunori Murakami, Yuji Baba, Kanta Urakami, Nobuya Niizaki, Hirofumi Natsume, Masato Arisawa